Who is a Chronic CO2 retainer

I found a neat chart that shows the difference between chronic CO2 retainers and those with acute CO2 retention that is probably reversible:

Likely CO2 Retention

1.  Usually severely limited by breathlessness
2.  Cor pulmonale
3.  Polycythemia
4.  FEV1 less than 1 liter
5.  Home nebulizers
6.  Home oxygen
7.  Abnormal blood gases when well
8.  Admission blood gases show high CO2 and High HCO3 (example:  CO2 50, HCO3 32)
9.  Vital signs not different from normal
10.  Saturations not different from normal
11.  Reasonable air entry
12.  It's reasonable to maintain an SpO2 of 88-92%
13.  Disease generally complicated with either asthma or heart failure

Likely Ventilatory Failure

1.  Not usually limited by breathlessness
2. No signs of chronic hypoxemia
3.  FEV1 good
4.  Inhalers only at home
5.  Normal blood gases when well
6.  CO2 and HCO3 consistent with critical ill
7.  Critically ill
8.  Silent chest or feeble chest movement
9.  Dubious diagnosis of COPD
10.  Chest x-ray shows pulmonary edema or severe pneumonia
11.  It's reasonable to provide these patients with whatever oxygen they require to maintain adequate oxygenation

Studies show that of those COPD patients who present to the hospital in acute respiratory distress, about 50 percent have acute CO2 retention that is reversible with treatment, and about 50 percent are chronic CO2 retainers. 

Reference:

1. Cooper, Nicola, Kirsty Forrest, Paul Cramp, "Essential guide to acute care," 2nd edition, 2006, Massachusetts, page 24.  The authors also support the idea that the hypoxic drive theory is a hoax, and thus the reason for the explanation of CO2 retention.